JP2005316281A - Sleeve for optical splicing, and optical receptacle and optical module using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sleeve for optical splicing which can be shortened, and to provide an optical receptacle and an optical module using the sleeve. <P>SOLUTION: The sleeve 15 for optical splicing is formed cylindrical and is engaged and abutted on two optical ferrules 3, 4 at both ends and thereby splices these two optical ferrules 3, 4 to each other. One of the ferrule engagement parts 21, 22 to be engaged with the optical ferrules 3, 4 is increased in engagement holding force per unit length more than the other. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical optical connection sleeve used for connecting two optical ferrules, an optical recess pull and an optical module using the optical connection sleeve, and in particular, making the connection between optical ferrules compact. For improvements.

  As a coupling device between an optical connector and an optical semiconductor element, an optical resector pull is widely used. In this optical recess pull, a configuration using a cylindrical optical connection sleeve has been proposed in order to align and butt-connect two optical ferrules concentrically (see, for example, Patent Document 1). ).

FIG. 18 shows a conventional example of such an optical connection sleeve.
The optical connection sleeve 1 has a cylindrical shape in which the inner diameter d is slightly smaller than the outer diameter D of the two optical ferrules 3 and 4 to be connected, and a part of the peripheral wall is cut along the axial direction. It is the structure which has 1a (slit) (for example, refer patent document 2).
The separation part 1a is for making the peripheral wall of the optical connection sleeve 1 easily expand its diameter by elastic deformation when the optical ferrules 3 and 4 are fitted to both ends of the optical connection sleeve 1.

  As shown in the figure, the conventional optical connection sleeve 1 has a first ferrule fitting portion 5 for fitting an optical ferrule 3 on one end side and a second ferrule fitting for fitting an optical ferrule 4 on the other end side. It is a joint part 6. The conventional optical connection sleeve 1 has a cylindrical shape with a uniform thickness over its entire length, and when the optical ferrules 3 and 4 are fitted to the ferrule fitting portions 5 and 6, the ferrule fitting portions 5 and 6 are fitted. The fitting and gripping force per unit length generated by the elastic deformation of the ferrule does not differ between the ferrule fitting portions 5 and 6.

Accordingly, the ferrule fitting portions 5 and 6 are fitted with the fitting lengths of the ferrule fitting portions 5 and 6 so as to obtain a necessary gripping force so that the optical ferrules that are fitted and connected do not inadvertently fall off. L1 and L2 are set.
In the conventional case, the fitting length L1 and the fitting length L2 are set substantially equal.

JP 9-33759 A JP 2002-116351 A

By the way, in order to realize high-density mounting of the connection portions between the optical ferrules, there is an increasing demand for downsizing of optical less sectors and optical modules.
In order to realize a compact optical resector pull and an optical module, it is important to shorten the length of the optical connection sleeve used there.
However, in the optical connection sleeve 1 described above, in order to ensure the fitting gripping force required for each ferrule fitting portion 5, 6, an equivalent fitting length L 1 for each ferrule fitting portion 5, 6. , L2 must be secured, and as a result, there is a problem that it is difficult to reduce the length of the optical connection sleeve 1.

  An object of the present invention is to provide an optical connection sleeve that can be shortened by setting the fitting length of one ferrule fitting portion to be shorter than the fitting length of the other ferrule fitting portion. It is an object of the present invention to provide an optical recess pull and an optical module that are made compact by using the shortened optical connection sleeve.

In order to achieve the above object, the optical connection sleeve according to the first aspect of the present invention is formed in a cylindrical shape, and two optical ferrules are fitted and abutted at both ends thereof to thereby make the two optical ferrules. An optical connection sleeve for mutual connection,
One of the ferrule fitting portions at both ends into which the optical ferrule is fitted is characterized in that the fitting grip force per unit length is larger than the other.

  The optical connection sleeve according to claim 2 of the present invention is the optical connection sleeve according to claim 1, wherein the thickness around one ferrule fitting portion is changed to the thickness around the other ferrule fitting portion. The fitting grip force of one ferrule fitting part may be larger than the fitting grip force of the other ferrule fitting part.

  The optical connection sleeve according to claim 3 according to the present invention is the optical connection sleeve according to claim 1 or 2, wherein the peripheral wall of at least one ferrule fitting portion is separated along the axial direction. Depending on the presence or absence of the separation part or the difference in the size of the separation part provided on the peripheral wall of both ferrule fitting parts, the fitting gripping force of one ferrule fitting part is changed to that of the other ferrule fitting part. It is good to make it larger than the fitting grip force.

  The optical connection sleeve according to a fourth aspect of the present invention is the optical connection sleeve according to the third aspect, wherein the separating portion includes a first slit extending along the axial direction on a cylindrical peripheral wall, The structure may include a second slit extending in a circumferential direction from a part of the first slit.

  The optical connection sleeve according to claim 5 according to the present invention is the optical connection sleeve according to claim 1 or 2, wherein the inner peripheral surface of at least one of the ferrule fitting portions is an outer peripheral surface of the optical ferrule. A groove that secures a gap between the ferrule and one of the ferrules depending on the presence or absence of the groove or the difference in the friction area corresponding to the amount of the groove provided on the inner peripheral surface of both ferrule fitting portions. The fitting grip force of the fitting portion may be larger than the fitting grip force of the other ferrule fitting portion.

  An optical leasing pull according to a sixth aspect of the present invention includes the optical connection sleeve according to any one of the first to fifth aspects, and an optical ferrule inserted at both ends of the optical connection sleeve. The insertion length is different.

  According to a seventh aspect of the present invention, there is provided an optical module comprising the optical recess pull according to the sixth aspect.

In the optical connection sleeve according to the present invention, the thicknesses of the ferrule fitting portions at both ends are different from each other as described in claim 2, or the equipment of the disconnection portion is changed as described in claim 3. So, one of the ferrule fitting parts at both ends has a larger fitting grip force per unit length than the other, and the fitting length could be set shorter than the other, instead, If the fitting length is set shorter than the other, the fitting gripping force per unit length is the same in both ferrule fitting parts, so that both ferrule fitting parts have equal fitting lengths. Compared with the conventional sleeve for optical connection which had to be ensured, the length can be shortened.
By using the shortened optical connection sleeve of the present invention for the optical recess sector and the optical module, the optical recess sector and the optical module can be made compact, and the optical ferrules can be connected to each other at a high density. be able to.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an optical connection sleeve according to the present invention and an optical recess pull and an optical module using the sleeve are described in detail below with reference to the drawings.
FIG. 1 is a longitudinal sectional view of a first embodiment of an optical less sector pull using an optical connection sleeve according to the present invention, and FIG. 2 is an embodiment in which two optical ferrules are fitted to the optical connection sleeve shown in FIG. FIG. 3 is a longitudinal sectional view showing a state in which one optical ferrule is fitted to one thickened ferrule fitting portion of the optical connection sleeve shown in FIG.

  This optical recess pull 11 is obtained by accommodating and holding an optical connection sleeve 15 according to the present invention in a resin case 13. The optical connection sleeve 15 accommodated in the case 13 is prevented from coming off by a metal holding member (bush) 17 fitted to one end of the case 13.

As shown in FIG. 2, the optical connection sleeve 15 is formed in a substantially cylindrical shape, and the two optical ferrules 3 and 4 are fitted and abutted at both ends thereof, so that the two optical ferrules 3 and 4 are mutually connected. Connect. The optical ferrules 3 and 4 have an optical fiber 8 inserted through the central axis thereof.
In the optical connection sleeve 15 of the present embodiment, one ferrule fitting portion 21 is longer than the other ferrule fitting portion 22 in the ferrule fitting portions 21 and 22 at both ends where the optical ferrule is fitted. Increase the fitting gripping force (elastic force toward the direction of diameter reduction when deformed in the diameter expansion direction), and instead make the fitting length L3 shorter than the other fitting length L4. It is set.

  More specifically, in the case of the present embodiment, as shown in FIG. 3, the thickness t1 around one ferrule fitting portion 21 is greater than the thickness t2 around the other ferrule fitting portion 22. Is set larger, the fitting gripping force of one ferrule fitting part 21 is made larger than the fitting gripping force of the other ferrule fitting part 22.

  The optical connection sleeve 15 is equipped with a separating portion 24 that cuts the peripheral wall along the axial direction. The separation part 24 is used to make the peripheral walls of the ferrule fitting parts 21 and 22 easily expand in diameter by elastic deformation when the optical ferrules 3 and 4 are fitted to the ferrule fitting parts 21 and 22. is there. The separating part 24 is formed in a thin slit shape having a constant width and is formed over the entire length of the sleeve 15.

  The raw material of the optical connection sleeve 15 may be a ceramic material, a metal material, a glass material, a plastic material, or the like, but in order to facilitate elastic expansion and contraction in the radial direction when formed from any raw material, It is effective to equip the separation part 24.

The above-mentioned optical connection sleeve 15 has different thicknesses between the ferrule fitting portions 21 and 22 at both ends, so that one of the ferrule fitting portions 21 and 22 at both ends is per unit length more than the other. The fitting grip force is increased. Instead, the fitting length L3 is set to be shorter than the other fitting length L4, and the fitting grip force per unit length is at both ferrule fitting portions. Compared to a conventional sleeve for optical connection that has to ensure the same fitting length in each of the ferrule fitting portions for the same reason, the length can be reduced.
In the optical recess pull 11 using the optical connection sleeve 15, the insertion lengths of the optical ferrules 3 and 4 inserted at both ends of the optical connection sleeve 15 are different, and the insertion length of one optical ferrule 3 is small. Thus, the size of the case 13 can be reduced by reducing the length of the optical connection sleeve 15 to achieve compactness, and high-density mounting of the connection portions between the optical ferrules can be realized.

In addition, the specific form which makes the thickness between ferrule fitting parts 21 and 22 different is not restricted to a structure as shown in FIG.
For example, like the optical connection sleeve 31 shown in FIG. 4, a tapered tube structure in which the inner diameter d1 is constant and the outer diameter d2 is gradually reduced from one end side to the other end side is obtained. The thicknesses of the ferrule fitting portions 21 and 22 may be different from each other.
Further, like the optical connection sleeve 32 shown in FIG. 5, a cylindrical body having a constant inner diameter and outer diameter is used, and the outer peripheral surface on the other end side of the cylindrical body is chamfered 33 so that the ferrule is fitted. You may make it make the thickness of the part 22 thinner than the thickness of the ferrule fitting part 21 of the one end side.

Moreover, the specific means for giving a difference in the fitting grip force between the ferrule fitting parts 21 and 22 is not limited to the method of giving a difference in the wall thickness as described above.
For example, like the optical connection sleeve 35 shown in FIG. 6, the peripheral wall of the ferrule fitting portion 22 on the other end side where the fitting and gripping force is to be weakened is arranged along the axial direction in addition to the common separating portion 24. An extending separating portion 36 may be added, and the fitting / gripping force of one ferrule fitting portion 21 may be made larger than the fitting / gripping force of the other ferrule fitting portion 22 depending on the presence / absence of the separating portion 36. .
Although not shown in the drawings, the opening width of the common separating portion 24 extending from one end to the other end of the sleeve is set so that the other end side is larger than the one end side, and both ferrule fitting portions are Depending on the size of the separating portion 24 provided on the peripheral wall, the fitting / gripping force of one ferrule fitting portion 21 may be made larger than the fitting / gripping force of the other ferrule fitting portion 22. .

Further, the separation portion provided on the peripheral wall of the optical connection sleeve is not limited to the one extending along the axial direction of the sleeve.
For example, like the optical connection sleeve 38 shown in FIG. 7, the separating portion 24 includes a first slit 24a extending along the axial direction on a cylindrical peripheral wall, and a circumferential direction from a part of the first slit 24a. The second slit 24b extends and the second slit 24b is provided on the other end side, or the number of the second slits 24b is different between the ferrule fitting portion 21 and the ferrule fitting portion 22. By doing so, the fitting / gripping force of one ferrule fitting part 21 may be made larger than the fitting / gripping force of the other ferrule fitting part 22.

Further, as shown in the above embodiment, the separation portion 24 provided on the peripheral wall of the sleeve does not need to penetrate from one end of the sleeve to the other end.
For example, as in the optical connection sleeve 41 shown in FIG. 8, the separation part 24 may be provided only in the ferrule fitting part 22 on the other end side where it is desired to weaken the fitting and gripping force.
Further, as in the optical connection sleeve 44 shown in FIG. 9, the ferrule fitting portion 22 on the other end side where the fitting and gripping force is desired to be weakened has an auxiliary extending along the axial direction in addition to the main separation portion 24. The separating portion 45 may be added to adjust the fitting and gripping force to a desired magnitude.
Further, like the optical connection sleeve 47 shown in FIG. 10, an auxiliary detachment portion 48 extending in the circumferential direction from the main detachment portion 24 is added to adjust the fitting and gripping force to a desired magnitude. Also good.
In the optical connection sleeves 41, 44, and 47 shown in FIGS. 8 to 10, the fitting gripping force of one ferrule fitting portion 21 is generated by press-fitting the optical ferrule.

Further, an optical connection sleeve according to the present invention is fitted to a cylindrical body 53 having a peripheral wall provided with a separation portion 24 along the axial direction, as in the optical connection sleeve 51 shown in FIG. It is good also as a structure provided with the separate reinforcement ring 54 to which it wore. The reinforcing ring 54 increases the fitting and gripping force of the ferrule fitting portion 21 on one end side, and produces the same action and effect as when the thickness of the peripheral wall of the ferrule fitting portion 21 is increased.
The reinforcing ring 54 has a separation portion 54a in a part of the peripheral wall, and is fixed to the outer periphery of the cylindrical body 53 by press-fitting.
In order to adjust the fitting and gripping force, as shown in the optical connection sleeve 55 shown in FIG. 12, the reinforcing ring 54 may be provided with an auxiliary detachment portion 54b.

  Further, as in the optical connection sleeve 57 shown in FIG. 13, at least the inner peripheral surface of the ferrule fitting portion 22 on the other end side is formed with a groove 58 that secures a gap with the outer peripheral surface of the optical ferrule. The fitting of one ferrule fitting portion 21 depends on the presence or absence of the groove 58 or the difference in the friction area corresponding to the amount of the groove 58 provided on the inner peripheral surface of both ferrule fitting portions 21 and 22. It is good also as a structure which made the gripping force larger than the fitting gripping force of the other ferrule fitting part 22.

In the optical connection sleeve 57 shown in FIG. 13, the groove 58 is formed along the axial direction of the cylinder. However, the groove formed to reduce the friction area with the optical ferrule is shown in FIG. A groove 63 extending in the circumferential direction may be used as in the optical connection sleeve 61 shown in FIG.
The circumferentially extending groove 63 may be a continuous spiral groove like a female screw groove.

In each of the above-described optical connection sleeves, the fitting grip force per unit length of the ferrule fitting portions 21 and 22 at both ends is changed, and instead the fitting length from one is fitted to the other. Although the length is set to be shorter than the length, the fitting length of the ferrule fitting portions 21 and 22 at both ends may be set to be the same so as to increase the difference in fitting and gripping force.
In addition, the difference of the fitting grip force of the ferrule fitting parts 21 and 22 of both ends can also be adjusted by changing the outer diameter of the ferrule to insert between the ferrule fitting part 21 side and the ferrule fitting part 22 side. It is.

Further, the use of the optical connection sleeve according to the present invention is not limited to the above-described optical recess sector.
For example, as shown in FIG. 15, by installing a light emitting / receiving element 65, which is one of the optical semiconductor elements, at one end of the optical recess pull 11, the light receiving / emitting module 66 can be used. By changing the optical semiconductor element connected to one end, it can be used for various optical modules.

Further, as shown in FIG. 16, the optical connection sleeve 15 according to the present invention is accommodated and held in the center of a holding case 71 open at both ends, so that the optical ferrules 3 and 4 can be inserted and removed from both ends. An adapter 73 can be configured.
Furthermore, as shown in FIG. 17, the optical connector and the optical ferrule are accommodated by housing and holding the optical connection sleeve 15 according to the present invention in a housing 76 having an elastic locking piece 75 for fitting and connecting the optical connector. An optical adapter 77 that is hung and connected can also be configured.

  The optical connection sleeve used in the coupling adapter or the optical adapter is not limited to the optical connection sleeve 15 shown in FIG. Needless to say, the various optical connection sleeves shown in FIGS. 4 to 14 can be used.

It is a longitudinal cross-sectional view of 1st Embodiment of the optical less sector pull using the sleeve for optical connection which concerns on this invention. FIG. 2 is an enlarged perspective view showing a form in which two optical ferrules are fitted to the optical connection sleeve shown in FIG. 1. FIG. 3 is a longitudinal sectional view showing a state where one optical ferrule is fitted to one thickened ferrule fitting portion of the optical connection sleeve shown in FIG. 2. It is a perspective view of 2nd Embodiment of the sleeve for optical connection which concerns on this invention. It is a perspective view of 3rd Embodiment of the sleeve for optical connection which concerns on this invention. It is a perspective view of 4th Embodiment of the sleeve for optical connection which concerns on this invention. It is a perspective view of 5th Embodiment of the sleeve for optical connection which concerns on this invention. It is a perspective view of 6th Embodiment of the sleeve for optical connection which concerns on this invention. It is a perspective view of 7th Embodiment of the sleeve for optical connection which concerns on this invention. It is a perspective view of 8th Embodiment of the sleeve for optical connection which concerns on this invention. (A) is a perspective view of 9th Embodiment of the sleeve for optical connection which concerns on this invention, (b) is A arrow directional view of Fig.11 (a). It is a perspective view of 10th Embodiment of the sleeve for optical connection which concerns on this invention. (A) is a perspective view of an eleventh embodiment of an optical connection sleeve according to the present invention, (b) is a BB cross-sectional view of FIG. 13 (a), and (c) is C of FIG. 13 (a). It is -C sectional drawing. (A) is a longitudinal sectional view of a twelfth embodiment of the optical connection sleeve according to the present invention, (b) is a sectional view taken along the line DD of FIG. 14 (a), and (c) is a sectional view of FIG. It is EE sectional drawing. It is a longitudinal cross-sectional view of the optical module which uses the optical sector pull shown in FIG. FIG. 3 is a longitudinal sectional view of a coupling adapter using the optical connection sleeve shown in FIG. 2. It is a longitudinal cross-sectional view of the optical connector using the sleeve for optical connection shown in FIG. It is a perspective view which shows the structure of the conventional sleeve for optical connection.

Explanation of symbols

3,4 optical ferrule 8 optical fiber 11 optical recess pull 13 case 15 optical connection sleeve 17 holding member (bush)
21 Ferrule fitting part 22 Ferrule fitting part 24 Separation part 24a 1st slit 24b 2nd slit t1, t2 Thickness 31,32,35,38 Optical connection sleeve 36 Separation part

Claims (7)

An optical connection sleeve that is formed in a cylindrical shape and that connects two optical ferrules at both ends thereof to make contact with each other,
One of the ferrule fitting parts of the both ends with which an optical ferrule fits has the fitting grip force per unit length larger than the other, The optical connection sleeve characterized by the above-mentioned.   By setting the wall thickness around one ferrule fitting part to be larger than the wall thickness around the other ferrule fitting part, the fitting gripping force of one ferrule fitting part can be adjusted to that of the other ferrule fitting part. The optical connection sleeve according to claim 1, wherein the sleeve is larger than the fitting and gripping force.   The peripheral wall of at least one ferrule fitting part is provided with a cutting part along the axial direction, the presence or absence of the cutting part, or the difference in the size of the cutting part provided on the peripheral wall of both ferrule fitting parts, 3. The optical connection sleeve according to claim 1, wherein the fitting gripping force of one ferrule fitting part is larger than the fitting gripping force of the other ferrule fitting part.   The said separating part is a structure provided with the 1st slit extended along an axial direction on a cylindrical surrounding wall, and the 2nd slit extended in the circumferential direction from a part of this 1st slit, It is characterized by the above-mentioned. 3. An optical connection sleeve according to 3.   On the inner peripheral surface of at least one ferrule fitting portion, a groove is formed to ensure a gap with the outer peripheral surface of the optical ferrule, and the presence or absence of the groove or the inner peripheral surface of both ferrule fitting portions is provided. The fitting gripping force of one ferrule fitting part is made larger than the fitting gripping force of the other ferrule fitting part due to a difference in friction area corresponding to the size of the groove. The optical connection sleeve according to claim 1 or 2.   6. An optical recessive pull comprising the optical connection sleeve according to claim 1, wherein insertion lengths of optical ferrules inserted at both ends of the optical connection sleeve are different. An optical module comprising the optical sector pull according to claim 6.

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